**5. Conclusions and perspectives**

Rejected agricultural by-products offer multiple opportunities for recovery and have significant potential not only in the agricultural and agrifood sectors but also in plant protection. In fact, in this work, crude OMW tested against *A. pomi* were effective in reducing the level of their populations to economically tolerable levels. However, the effect of products tested in nursery pest management must be compatible with integrated pest management (IPM) concept. Since, some plant producers also carry out augmentative releases of natural enemies (Unpublished data). Therefore, like conventional pesticides, risk assessment of side effects of OMW is still necessary [17, 18]; the evaluation of the effects of OMW on non-target organisms must include both lethal and sublethal effects (e.g., [14, 15]). In the event that the natural enemies bred massively and purchased by plant producers, their releases must be carried out outside the treatment periods. It is also possible to spray against pests with OMW outside the activity of natural enemies; preferably during vegetative rest against overwintering forms.

Moreover, knowing that OMW can also show phytotoxicity [69], an evaluation in this direction is planned. Our work can help to enhance the use of MOW to control the green apple aphid among other pests while integrating the ecological services provided by beneficial organisms in agroecosystems, and at the same time avoid the harmfulness of OMW. At the industrial level, the large-scale direct extraction of polyphenols for the production of biopesticides would result in high addedvalue. The identification and quantification of the constituents of polyphenols with their biochemical modes of action in treated pests should precede the economic estimation of pest control based on OMW and their polyphenols.
